JPH0321493A - Optical recording medium - Google Patents

Abstract

PURPOSE:To enhance repeating recording characteristics and to obtain stable signal intensity even when recording laser power is changed by successively providing an optical recording layer containing a specific naphthalocyanine polymer compound and the deformation control layer of said optical recording layer on a transparent substrate. CONSTITUTION:An optical recording layer containing at least one kind of a naphthalocyanine polymer compound represented by formula and the deformation control layer thereof are formed on a transparent substrate in this order. In the formula, R<1-3>, R<10-12> and R<16-17> are a hydrogen atom or an alkyl group which may have a substituent, R<13-15> is an alkyl group which may have a substituent or a polyether group, g-k are an integer of 1 or more, n is an integer of 1 or more to show the polymerization degree of a polymer and l and m are respectively independently an integer of 0-6 to show the number of substituents Z<1>, Z<2>. When the optical recording layer is irradiated with recording laser beam, the flocculation state of the dye is changed to make recording possible.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an optical recording medium on which information can be written and read by changing the aggregation state of molecules in an optical recording layer by irradiation with a laser beam.

TECHNICAL BACKGROUND OF THE INVENTION AND PROBLEMS There have been various known optical recording media that record and read information using laser beams. One method is to irradiate the recording layer on the substrate with a laser beam,
Optical recording media are known that perform recording by causing changes such as melting, evaporation, and decomposition in the irradiated area.

For example, JP-A-57-112098, JP-A-58
-56892 publication, Japanese Patent Application Laid-open No. 60-89842,
JP-A-60-150243 discloses an optical recording medium comprising a transparent substrate and an optical recording layer formed of an organic dye thin film layer provided on the substrate. Apply a laser beam with a relatively long wavelength, for example 780 nm or more, to the optical recording layer! ! A is used to write and read information. In such optical recording media, organic dyes are melted and
By evaporating, decomposing, etc., minute pits are easily formed in the optical recording layer.

However, in the above-mentioned optical recording medium, recording is performed by forming bits in the optical recording layer that change the shape of the recording layer, so when recording is repeatedly performed on this optical recording medium, the recording characteristics change significantly. There was a problem that it was decreasing. Furthermore, in order to obtain stable signal strength, a high laser parker is required, and there is also the problem of poor sensitivity.

The present inventors conducted extensive research to solve the above-mentioned problems, and found that at least one naphthalocyanine-based polymer compound represented by the following general formula [I] was coated on a transparent substrate.
In an optical recording medium in which an optical recording layer containing at least one of the above species and a deformation suppressing layer of the optical recording layer are provided in this order, when the optical recording layer is irradiated with a recording laser, the optical recording layer It is possible to perform recording by changing the aggregation state of the dye rather than by forming bits (holes). Therefore, it has excellent repeat recording characteristics and stable signal intensity even with low recording laser power. The present invention was completed based on the discovery that

Purpose of the Invention The present invention aims to solve the problems associated with the prior art as described above. Rather than recording, it is possible to record by changing the state of aggregation of the dye in the optical recording layer. Therefore, it has excellent repeat recording characteristics, and moreover, it is possible to obtain stable signal strength even when the recording laser power changes. The aim is to provide an optical recording medium.

Summary of the Invention The optical recording medium according to the present invention contains at least 1w of a naphthalocyanine polymer compound represented by the following general formula [I].
It is characterized in that an optical recording layer containing one or more of the above components and a deformation suppressing layer of the optical recording layer are provided in this order.

In the formula c, M is S i s, Ge or Sn. X
is -OSIR1R20 (C 2 is -(OSIR' R2) each independently has one R11 and the substituent z1 l2 +140) jOSIR R O-, and also I2 kO-. Y, Y is so-Of? In -OSIR'Rl4R', l2Zz are each independently a halogen atom or -Rte-ORt'y. Here, RI R2 3 , . ,,,,R1
0 R11 R12 R16R and Rl7 may be the same or different from each other and are a hydrogen atom, an alkyl group that may have a substituent, an aryl group, an acyl group, a cycloalkyl group, and Rl3R
l4 and R15 may be the same or different and are an alkyl group, an aryl group, an acyl group, a cycloalkyl group, an alkoxy group, or a polyether group which may have a substituent, and g, h, i and jSk may be the same or different, and are an integer of 1 or more, preferably an integer of 1 to 7, more preferably an integer of 1 to 3. Further, n is an integer of 1 or more, indicating the degree of polymerization as a polymer, preferably an integer of 1 to 10, more preferably an integer of 1 to 3.

flSm is each independently an integer of 0 to 6, and is the number of substituents z1 and z2. ] Detailed Description of the Invention First, the optical recording medium according to the present invention will be described in detail.

In the present invention, the transparent substrate used is a substrate that has a light transmittance of 85% or more for writing or reading information and has small optical anisotropy, which is commonly used as a substrate for optical recording media. It will be done. Specific examples of such transparent substrates include glass, acrylic resin, polycarbonate resin, polyester resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, polystyrene resin, and polyolefin resin such as poly4-methylpentene. - A substrate made of a non-quality polyolefin resin, a thermoplastic resin such as a polyethersulfone resin, or a thermosetting resin such as an epoxy resin or an allyl resin as shown in US Pat. No. 4,614,778 is used. Among these, it is preferable to use a non-quality polyolefin resin substrate because of the variety of solvents that can be used when dissolving the dye.

The thickness of such a transparent substrate is not particularly limited, and its shape may be plate-like, film-like, circular or card-like, and its size is not particularly limited. There are no restrictions. In addition, the transparent substrate is usually provided with guide grooves for position control during recording and reading, and unevenness for preformatting such as address signals and various marks. It can be applied using a stun bar or the like when molding the thermoplastic resin by injection molding, compression or shaping.

The optical recording medium according to the present invention has an optical recording layer and a deformation suppressing layer of the optical recording layer provided in this order on a transparent substrate as described above, and this recording layer has the following general formula [I]. An optical recording layer containing at least one of the specific naphthalocyanine polymer compounds shown and a deformation suppressing layer of the optical recording layer are provided in this order.

[Wherein, M is S1sGe or Sn. X
is 12 1 2
is -(OSIR R ) 0-. Y
SY isok Each independently -R11 -OR12 -OSIR1
3R14R15 and substitution 2! ZZ2 is each independently a norogen atom or , -Rl6 -01? It is l7. Here, 2 3 10
11 12 1[IR',R,R
......R SR, RR and Rl7 may be the same or different from each other, hydrogen atom, alkyl which may have a substituent, aryl group, acyl group, cycloalkyl 13 14 RR and R15 may be the same or different and are an alkyl group, an aryl group, an acyl group, a cycloalkyl group, an alkoxy group, or a polyether group which may have a substituent, and gSh ．． ,ls
JSk may be the same or different from each other, and 1
The above integer is preferably an integer of 1 to 7, more preferably an integer of 1 to 3. Further, n is an integer of 1 or more,
It indicates the degree of polymerization as a polymer, and is preferably an integer of 1 to 10, more preferably an integer of 1 to 3.

Rsm is each independently an integer of 0 to 6, and substituent 2
and the number of Z2. ] 1 1 17 Here, to explain in more detail about R - R and z1 to z2 as described above, specific examples of the halogen atom in the above formula include chlorine, bromine, iodine, fluorine, etc., and substituents Specific examples of the alkyl group which may have include methyl group, stearyl group, n-
butyl group, tert-butyl group, tert-amyl group,
Examples include 2-ethylhexyl group, trichloromethyl group, 1-refluoromethyl group, 2-methoxyethyl group, etc.
Specifically, the aryl group includes a phenyl group, a tolyl group, a naphthyl group, an anthryl group, a chlorophenyl group,
Examples include hydroxyphenyl group, diethylaminophenyl group, hydroxynaphthyl group, dimethylaminonaphthyl group, diethylaminonaphthyl group, etc., and specific examples of the cycloalkyl group include cyclohexyl group, cyclopentyl group, cyclobutyl group, etc. Specific examples of the acyl group include an acetyl group, trifluoroacetyl group, etc. Specific examples of the alkoxy group include a methoxy group, ethoxy group, butoxy group, stearyloxy group, etc. Specific examples of the ether group include, but are not limited to, diethylene glycol monoethyl ether group and triethylene glycol monobutyl ether group.

The compound represented by general formula [I] can be synthesized by the following method.

For example, first, a phthalocyanine compound represented by the general formula [ml] is synthesized from an isoindolenine compound represented by the following general formula [nl] and various metal salts.

General formula [IN]Ht:! I-IN (In the formula, Z, m and g are the same as l2 2 or Z mSfI in the general formula [I].) Also, using carboxylic acid anhydride, imide or 21-lyl as a raw material, General formula [I11] can also be obtained according to a conventional method.

General formula [III] (where M, ZSρ and m are M in general formula [I]
, ZS, QSm. ) Next, after reacting the obtained naphthalocyanine compound represented by the general formula [III] with a compound that can serve as a divalent linkage, the terminal hydroxyl group is alkylated or silylated to form a general A naphthalocyanine-based polymer compound represented by formula [I] can be obtained.

A typical example of the naphthalocyanine polymer compound represented by the general formula [I] used in the present invention is the following compound (a).

~(d) etc. -f'SJ' 2 % O Further, the optical recording layer of the optical recording medium according to the present invention may contain a polymer binder, if necessary. Examples of such polymeric binders include vinyl chloride resins, acrylic resins, polyester resins, polyamide resins, polycarbonate resins, epoxy resins, methacrylic resins, vinyl acetate resins, nitrocellulose, and phenol resins. When using such a polymer binder, the content of the polymer binder in the optical recording layer should be 10 ffl% or less, as the polymer binder may inhibit thermal movement and scooking of the dye molecules. It is preferable that

The thickness of the optical recording layer formed on the transparent substrate is desirably 10 μm or less, preferably 500 to 2 μm.

In the optical recording medium according to the present invention, a deformation suppressing layer for the optical recording layer is provided on the optical recording layer as described above.

Such a deformation suppressing layer of the optical recording layer prevents deformed parts such as holes from being formed in the laser beam irradiated part of the optical recording layer when the laser beam is irradiated for recording on the optical recording layer. playing a role.

Specifically, such a deformation suppressing layer is made of SiO
, SiO, oxides such as ZnO, nitrides such as S t 32 N 4, A II N - T t N,
Carbides such as SiC and TiC, dielectrics such as thermoplastic resins and thermosetting resins, or T e -. S e %
Chalcogen compounds containing S and the like, semiconductor materials made of compounds such as Ge and St, and metals such as gold, silver, copper, platinum, aluminum, cobalt, and nichrome are used.

Among these, dielectric or semiconductor materials with low thermal conductivity are particularly preferred in order to reduce the influence of thermal diffusion of laser light.

These deformation suppressing layers may be used as a single layer, or may be used in a stacked manner.

The thickness of the deformation suppressing layer is about 0.01 to 10 μm, preferably about 0.02 to 1.0 μm.

By providing the deformation suppressing layer as described above on the optical recording layer, pits (holes) are not formed in the optical recording layer when the optical recording layer is irradiated with a recording laser beam.
The state of aggregation of the naphthalocyanine polymer compound contained in the optical recording layer changes, making it possible to perform recording.

Further, in the present invention, a deformation suppressing layer as described above can be provided between the transparent substrate and the optical recording layer, and by providing the deformation suppressing layer between the transparent substrate and the optical recording layer, the optical recording It is possible to further suppress a change in shape of the optical recording layer when the layer is irradiated with a recording laser beam.

Next, a method for manufacturing an optical recording medium according to the present invention will be explained.

First, a dye solution is prepared by dissolving or dispersing the naphthalocyanine polymer compound as described above in an organic solvent. At this time, the organic solvent has a low boiling point, preferably 200°C.
More preferably, an organic solvent having a boiling point of below 150° C. is used. Specifically, the following organic solvents are used.

(1) Alcohols such as methanol, ethanol, l-probanol,
1-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, etc.

(1) Ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone.

(i1) Amides such as dimethylformamide, dimethylacetamide, etc.

(IV) Sulfoxides For example, dimethyl sulfoxide.

(V) Ethers such as diethyl ether, dipropyl ether, dibutyl ether, etc.

(v1) Esters For example, ethyl acetate, probyl acetate, etc.

(■) Aliphatic halogenated hydrocarbons such as 1,2-dichloroethane, methyl chloride, carbon tetrachloride, chloroform, dichlorobenzene, etc.

(V1) Aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene.

These organic solvents may be used alone or in a mixture at a certain ratio.

Further, a polymer binder may be added to the dye solution as described above, if necessary.

Next, the optical recording layer according to the present invention can be formed by applying the dye solution prepared as described above onto a transparent substrate and drying to remove the organic solvent from the dye film. To apply the dye solution onto a transparent substrate,
For example, a spin coating method, a dip method, a spray method, etc. can be employed.

In the present invention, the recording layer thus formed on the transparent substrate can also be heat-treated at 80 to 280°C, preferably 100 to 250°C, by external heating.

The heating time varies greatly depending on the heating temperature, but is usually preferably about 30 seconds to 90 minutes, more preferably about 3 to 60 minutes. There are no particular restrictions on the method of heating the recording layer from the outside, including a method using a heating oven, a method of bringing the recording layer into contact with a heating roll or a hot plate, a method of irradiating the recording layer with infrared rays using an infrared lamp,
A method such as heat pressing can be adopted.

When the recording layer is heat-treated to a temperature of 80 to 280° C. in this manner, the optical properties and stability of the recording layer may be improved. This is achieved by heat-treating the recording layer.
It is presumed that this is because the state of molecular assembly inside the recording layer becomes more dense.

The heat treatment of the recording layer is preferably carried out in an inert atmosphere such as nitrogen gas or an oxygen-containing atmosphere such as air.

After the recording layer is heat-treated at a temperature of 80 to 280°C as described above, the absorption wavelength of the recording layer is shifted to the longer wavelength side by exposing the recording layer to the vapor of an organic solvent such as chloroform, tetrahydrofuran, or toluene. In some cases, the sensitivity to light in the oscillation wavelength range of the semiconductor laser can be significantly improved.

Next, on the recording layer provided on the substrate as described above,
The deformation suppressing layer is formed by vacuum evaporation method, sputtering method, plasma CV
It is provided by a dry film method such as the D method or the ion blasting method, or by a spin coating method, a day soap method, a spray method, a roll method, or the like.

In order to record on the optical recording medium obtained as described above, the recording layer may be irradiated with a laser beam focused to about 1 μm, preferably a semiconductor laser beam. The aggregation state of the dye in the area irradiated with laser light changes, allowing information to be recorded. To reproduce the information recorded on the recording layer in this way, a laser beam or the like is irradiated to the area where information is recorded and the area where no information is recorded, and the difference in reflectance between them is read. It is carried out by

In the optical recording medium according to the present invention, information can be written again by slowly irradiating the recorded portion with a weak laser beam or by rapidly irradiating the recording area with a strong laser beam. In the optical recording medium according to the present invention, when the optical recording layer is irradiated with a recording laser, recording is performed not by forming pits in the optical recording layer, but by changing the aggregation state of the dye in the recording layer. Therefore, repeated recording is possible using the method described above.

The laser beam irradiated to the recording layer when reproducing information must have a lower energy than the laser beam used when writing information on the recording layer, and must not change the aggregation state of the recording layer when reproducing information. is preferred.

When writing or reproducing information to the recording layer, various lasers such as a He-Ne laser, a semiconductor laser, and a semiconductor laser can be used, but semiconductor lasers are particularly preferred in terms of cost and size. As a semiconductor laser, the center wavelength is 830 nm, 7
80 rv and shorter wavelength lasers can be used.

Effects of the Invention The optical recording medium obtained according to the present invention can be repeatedly recorded, and stable signal intensity can be obtained even with a low recording laser power.

[Examples] Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples.

In addition, in the examples, parts represent parts by weight.

Example 1 Preparation of naphthalocyanine polymer compound (b) To 50 parts of quinoline, 7.8 parts of tert-amyl-1,3-diiminobenziisoindoline and 5 parts of silicon tetrachloride were added.
．． 0 parts was added, heated and stirred at 180 to 20.0°C for 3 hours, cooled, diluted with 500 parts of methanol, filtered,
Washing with methanol and dimethylformamide and drying yielded 7.0 parts of tetra-tert-amyldihydroxysilicon phthalocyanine.

1.0 part of the obtained tetra-tert-amyldihydroxysilicon phthalocyanine and 5.0 parts of tri-101butylamine were added to 100 parts of pyridine, and while heating and stirring, 50 parts of pyridine was distilled off as a pre-distillation, and after cooling. , 8.0 parts of dichlorodimethylsilane was added, and 1
Stirred for 8 hours. Then, the temperature was gradually raised, and excess dichlorodimethylsilane was distilled off until the temperature in the system reached the boiling point of pyridine. The previously obtained tetratert-
Add 1.0 parts of amyldihydroxysilicon phthalocyanine, stir at room temperature for 3 hours, then reflux for 3 hours, cool, add 5.0 parts of trimethylchlorosilane, stir at room temperature for 12 hours, and dilute with 200 parts of methanol. The mixture was washed and dried to obtain a green powder.

The obtained powder was dissolved in chloroform, separated and purified using a silica gel ram, and then the solvent was distilled off to form a mixture of naphthalocyanine polymer compound (b) as a dimer and a small amount of trimer. I got the department.

A solution obtained by dissolving 2.0 parts of the obtained mixture of dimer (b) and trimer in 98.0 parts of dichloroethane was applied by spin coating onto a full disk substrate injection-molded with a non-quality polyolefin resin. At 600 rpm
An optical recording layer was formed by forming a film to a thickness of 1000 mm at rpm. On this recording layer, S t O 2 was deposited using a vacuum evaporation method.
was formed into a film with a thickness of approximately 100 μm, and then an ultraviolet curable resin was coated on top of this using the Subin coating method at a rotational speed of 400 rpa+, and was cured with an ultraviolet lamp to form a film with a thickness of 1.0 μm. Alternatively, an optical recording medium was obtained.

Example 2 Preparation of naphthalocyanine polymer compound (C) To 50 parts of hamaquinoline, 7.8 parts of tert-amyl-1,3-diiminobenzoisoindoline and 5 parts of silicon tetrachloride were added.
．． After heating and stirring at 180-200°C for 3 hours, cooling, diluting with 500 parts of methanol, filtering, washing with methanol and dimethylformamide, and drying, tetratart-amyl dihydroxy silicone was obtained. 7.0 parts of phthalocyanine were obtained.

To 100 parts of pyridine, 1.0 part of the obtained tetra-tert-amyldihydroxysilicon phthalocyanine and 5.0 parts of tri-n-butylamine were added, and while heating and stirring, 50 parts of pyridine was distilled off as a pre-distillation, and after cooling. , 860 parts of dichlorodimethylsilane were added, and the mixture was stirred at room temperature for 18 hours. Then, the temperature was gradually raised, and excess dichlorodimethylsilane was distilled off until the temperature in the system reached the boiling point of pyridine. Next, ethylene glycol 0
．． A mixture of 2 parts of pyridine and 30 parts of pyridine was added dropwise at 100°C over 60 minutes, heated under reflux for 4 hours, added with 3.0 parts of sodium ethoxide, heated under reflux for an additional 3 hours, and then cooled to room temperature. The raw material was poured into 500 parts of methanol, and the dark green precipitate was filtered off, washed with methanol, and dried to obtain a dark green dry powder.

The obtained dark green powder was dissolved in chloroform, separated and purified using a silica gel ram, and when the solvent was distilled off, the naphthalocyanine polymer compound (c) as a dimer and the trimer as a slight additive were separated. 0.5 part of the mixture was obtained.

A solution obtained by dissolving 2.0 parts of the resulting dimer (C) mixture with ε trimer in 98.0 parts of dichloroethane was spun onto a grooved disk substrate injection molded with a non-quality polyolefin resin. By coating method, rotation speed 600
A film was formed to a thickness of 950 μm using rpo+ to form an optical recording layer. Approximately 10% of SiO2 was deposited on this recording layer by vacuum evaporation.
A film was formed to a thickness of 0.06 mm, and on top of this, a hot melt adhesive MU 101 manufactured by Konishi Co., Ltd. was applied using a roll coater at a temperature of 160° C. to a thickness of approximately 25 μm.

Similarly, hot melt adhesive MU101 was applied with a roll coater onto a non-quality polyolefin resin disk substrate without an optical recording layer, and both disks were bonded together with the hot melt adhesive applied to each other to form an optical recording medium. And so.

Evaluation: Using a semiconductor laser with a wavelength of 830 nm,
Disc linear velocity 9.4 m/s, recording frequency 1. 0MHz
The laser was irradiated with an intensity of 1 to 10 mW. After this,
0. The signal was read using a laser with a power of 6 mW.

The results are shown in Figure 1.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between recording laser power and C/N ratio of an optical recording medium according to the present invention.

Claims (1)

[Claims] 1) An optical recording layer containing at least one naphthalocyanine polymer compound represented by the following general formula [I] and a deformation suppressing layer of the optical recording layer are provided on a transparent substrate. , in this order. ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [I] [In the formula, M is Si, Ge, or Sn. X is -O(
CH_2)_gO-, -O(C_2H_4O)_h-,
-OSiR^1R^2O (CH_2)_iOSiR^3
R^4O-, -OSiR^5R^6O(C_2H_4O
)_jOSiR^7R^8O-, or -(OSiR
^9R^1^0)_kO-. Y^1 and Y^2 are independently -R^1^1, -OR^1^2, -OSi
R^1^3R^1^4R^1^5, and the substituent Z^1
, Z^2 are each independently a halogen atom or -
R^1^6, -OR^1^7. Here, R^1,
R^2, ...... R^1^0, R^1^1, R^1
^2, R^1^6 and R^1^7 may be the same or different and represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group, an acyl group, a cycloalkyl group and R^1^3, R^1^4 and R^1^5
may be the same or different and are an alkyl group, an aryl group, an acyl group, a cycloalkyl group, an alkoxy group, or a polyether group which may have a substituent, and g, h, i, j and are integers of 1 or more which may be the same or different. Further, n is an integer of 1 or more and indicates the degree of polymerization as a polymer. l,
m is each independently an integer of 0 to 6, and represents a substituent Z^1
and the number of Z^2. ]